Thinning of a centrifugal blower used for an automobile or the like is strongly requested in order to mount the centrifugal blower in a limited space of a vehicle body. In the following description, the centrifugal blower used for the automobile or the like is also simply referred to as a centrifugal blower.
Further, strong requests described below are made to the centrifugal blower. In other words, noise reduction is requested to the centrifugal blower so that a passenger does not hear unpleasant noise. A countermeasure for rigidity against vibration generated when an automobile travels is requested to the centrifugal blower. Preventing infiltration of water into the centrifugal blower or accumulation of water outside the centrifugal blower caused by submergence or the like is requested to the centrifugal blower.
Conventionally, the centrifugal blower has prevented deterioration of a motor of the centrifugal blower or occurrence of abnormality in a circuit of the motor due to infiltration of water or salt through a flow channel. For example, PTL 1 discloses provision of a rubber vibration isolator on a mounting plate included in a motor as a countermeasure against vibration or noise caused by the vibration. The motor disclosed in PTL 1 is fastened to a fan case. With this configuration, the motor disclosed in PTL 1 can suppress vibration and prevent foreign matter from entering through a flow channel.
Other than the above, PTL 2 discloses a configuration in which a motor is mounted on an inside of a hub included in an impeller.